Automatic water strainer



May 11 1948 w. H. zoLLlNGER 2,441,526

AUTOMATIC WATER STRAINER Filed Aug. 9, 1944 5 Sheets-Sheet 1 Il/llrl Zallyef .May ll, 1948. w. |71'. zoLLlNGER ,2,441,526

AUTOMATIC WATER STRAINER yFiled Aug. 9. 1944 5 sheets-sheet 2 May 11, 1948 l w. H. zoLLlNGER 2,441,526

AUTOMATIC WATER STRAINER Filed Aug. 9. 1944 5 Sheets-Sheet 3 lul Il Enma/Wto@ Wazaa/#1220@ May lla 1948 w. H. zoLLlNGl-:R i 2,441,526

AUTOMATIC WATER STRAINER Fiied Aug. 9, 1944 5 sheets-sheet 4 mf/f@ AUTOMATIC WATER STRAINER Filed Aug. 9, 1944 5 Sheets-Sheet 5 Patented May 11, 1948 AUTOMATIC WATER STBAINEB Walter EZollinger, Bethlehem, Pa., assigner to Bethlehem Steel Company, a Pennsylvania poration application august 9, m4. serai Nb. 543,63

4 claims. (ci. 21o-152)' My invention relates in general to a new and improved straining apparatus for iluids, and

more particularly to an automatic self-cleaning f water strainer or lter.

Mechanical water strainers of all types tend to clog easily and require thorough. cleansing of their nlter surfacesv at more or less frequent intervals, depending largely, of course, upon the nature and quantity of the impurities to be separated, but generally several times every hour.

The best mode of accomplishing this is by back-washing with the filtered water, but as usually practiced this has certain disadvantages. Some strainers, for instance, continuously wash small segments of the nlter surface in rotation, which is wasteful of water and wearing on the nlter. Others back-wash at regularly timed intervals, which may or may not be the times when it is most needed. Virtually all require a number of tight-iitting special valves, such as sleeve valves, which clog easily, are quite expensive, and are now especially diillcult to `procure in large and oir-standard sizes.

One object of my invention, therefore, is a more eillcient large-capacity strainer which will automatically clean itself as required without wasting nltered water unnecessarily or interrupting the supply.

Another object is a pressure-responsive control mechanism which will back-wash the lter elements in a dennite predetermined sequence.

'A further object is a multiple-element strainer which is very simple and economical in construc' tion and operation, and with its maior operating parts easily accessible for repairs or changes.

Still other objects and purposes of this invention will appear hereinafter in the specification and in the appended claims.

Having above given a general description of the advantages of my invention, I shall'now in order to make the saine moreclear refer to the annexed nve sheets of drawings forming a part of this specification and in which like characters of reference indicate like parts:

Figure 1 is a sectional elevation of the strainer Fig. 2 is a top plan view of the strainer with the pumping unit and piping;

Fig. 3 is a' side elevation of the strainer show'- MAR 4 i952 ing the connection between the valve-operating cylinders and the pumping unit;

Fig. 4 is a sectional elevation of one of the valve-operating cylinders;

Fig. 5 is a side elevation showing the distributor valve piping;

Fig.' 6 is a diagrammatic view of the piping associated with the pumping unit, which unit is indicated in dotted lines;

Fig. 'I is a top plan view of the rotor of #the distributor valve:

Fig. 8 is a section taken on line 8'8 of Fig. '1;

Fig. 9 is a fragmentary section taken on the line 9-9 of Fis'. "I:

Fig. 10 isla top plan view -of the body portion of the distributor valve;

Fig. 11 is an inverted sectional elevation taken ontheline Il-II ofFig. 10;

Fig. 12 is a fragmentary section of one of the portsin the valve body;

Fig. 13 is an inverted side elevation of the gear reduction unit showing the cam and limit switch;

Fig. 14 is a side elevation of the reverse side of the gear reduction unit showing the distributor valve;

Fig. 15 is a section taken on the line I5-I5 of Fig. 13;`

Fig. 16 is a top plan view of the pumping unit;

Fig. 17 is a wiring diagram of the automatic pressure control means; and

Fig. 18 is a vertical section of the differential pressure controller used.

As shown in the drawings, my inventioncomprises broadly, in combination, the strainer I, the pressure differential controller 2, the pumping unit 3, the distributor valve 4, the back-wash valve actuating cylinders 5, 6 and 1, and their vassociated wiring and piping systems.

The strainer I comprises the substantially ovoid metal shell or casing 8, provided with the raw-water inlet pipe 9 andflltered-water outlet pipe III at its respective ends. Welded partition plates II and I2 divide the casing 8 into a raw-water chamber I3 and a ltered-water chamber I4. 'Ihe upper partition plate II and the bottom plate I5 are each provided with circular orices I8 adapted to receive the three open-ended perforated cylindrical filter baskets II, I8 and I9, which baskets may be constructed as shown in Fig. 1 of zinc-plated steel or the like 3 and are arranged to function normally in parallel to provide a large effective area. At the top of each said basket is located one of the strainer valves 20, which through the linkage means 2| is connected to one of the hydraulic cylinders 5, 6 or 1 for opening and closing said valve 20. These strainer valves 20 do not need to close tightly, as any leakage will not appreciably affect the operation, so the at metal discs shown will serve as well or better for'valve closures than' more expensive fittings. The open bottom of each basket is connected by the pipe 24, 25 or 26 to a back-Wash gate valve 21, 28 or 29, each of which is in turn connected to its respective hydraulic cylinders 5, =6 or 1 by the linkage 2| in such a manner that when its strainer valve 20 is opened the back-wash valve is closed, and vice versa.

The differential pressure controller 2 is of the ring-balance recorder type shown in Fig 18, and comprises a hollow ring-body 30 rotatably mounted on the knife edge bearing 3| and partially filled with a sealing fluid such as oil, mercury or the like. Said ring-body 30 -is divided by the upper partition 32 into the two compartments shown, one of which connects by flexible tube 33 to the inlet 9 and the other by similar tube 34 to the outlet I of the strainer The torque due to differences in pressure is opposed and partially balanced by the counterweight 35, the range of the control depending upon the size of said counterweight, which may be of any desired value.

As shown in the wiring diagram of Fig. 17, a

source of three-phase alternating current or other.

suitable current, provided with a disconnect switch 36, is connected to the magnetic starter 31, which is actuated by the mercury switch 38 on the pressure differential controller 2 to start the motor 39.' A mercury limit switch 40 in parallel with said switch 38 is adapted to be operated by the indented disc timer cam 4| as hereinafter described.

The pumping unit 3, as shown in Figs, 6 and I6, comprises the substantially rectangular reservoir or storage tank 42, supported on suitable' legs 43 or the like, and containing oil or other hydraulic fluid. Upon the top plate 44 of said tank is bolted screen cover plate 45 and plug 46 for filling the tank 42, and the electric motor 39, whose shaft 41 is connected by the pulley 48 and belt 49 to the gear reducer 50, and by the coupling to the rotary pump 52. The outlet 53 ofthe tank 42 is connected by the elbow 54, pipe 55, union 56, pipe 51, elbow 58 and pipe 59 to the input side of said pump 52, the output side of said pump connecting by the pipe 60, elbow 6|, and pipe 62 to the 'l' 63. One branch of said T 63 connects by the pipe 64, union 65, and pipe 66 to the distributor valve 4, and the other branch of said T 63 connects by the pipe 61 to the T 66. 'I'he pressure gauge 69 is mounted on the latter T 66, which connects by the pipe 10, union 1|, pipe 12, elbow 13, pipe 14, elbow 15, pipe 16 and coupling 11 to the pressure relief valve 16. barrel 19 of said relief valve 16 is perforated to relieve excessive pressure, which will push upward the plunger 80 against the spring washer 8| and the spring 82. The force of this spring 82 against the spring washer 63 is adjustable by means of the square-headed threaded rod 84 in the flanged nut 85 and secured to the top plate 44 and locked by the hexagonal nut 66, Oil from the distributor valve 4 is also returnable to the tank 42 through the coupling 81, bent pipe 88, elbow 89, and return pipe 90.

The

' |06 connecting to the pipe 66, a round rotor por- Referring to Figs. 13 to 15, inclusive, the electric motor se, through its shaft u, pulley 4a and belt 49, passing over the adjustable belttightening pulley 9|, is enabled to rotate the pulley 92 on the shaft 93 of the gear reducer 50. With particular reference to Fig. 15, it will be noted that the \upper pinion 94 on the shaft 93 is keyed thereto and drives the upper gear 95 on shaft 91, while all the other pinions on shafts 93 and 91 are keyed to the gears 95 with the gear 96 keyed to the shaft 91. The reduction in speed from the shaft 93 to the shaft 91 which is effected by said gear reducer 50 is from approximately 1135 R. P. M. to 0.830 R., P. M., or about 136715 to 1. end connected to the indented disc cam 4| actuating the mercury limit switch 40 an-d its lower end connected to the rotor 98 of the distributor valve 4.

Said distributor valve 4, for the three-basket strainer shown, is an eight-way bronze valve comprising a cover portion 99 having an inlet port tion 98 as in Figs. 7, 8 and 9 having a distributing aperture |0|. and a body portion |02 as in Figs. 10, 11 and 15, having the seven outlet ports |03, |04, |05, |06, |01, |08 and |09, Gland ||0, packing gasket |2, spring seat ||3 and spring ||4 permit operation without leakage or loss of pressure. 4

The outlet ports |03, |04, |05, |06, |01, and |06 connect in sequence through the piping ||5 to the lower and upper inlet openings ||6, 1, ||8, ||9, and |2| of the hydraulic cylinders 5, 6 and 1. Coupling 81 connects to the outlet port |09.

The hydraulic cylinders 5, 6 and 1 are identical in construction, as shown in Figs. 1 and 4. The piston |22 in each of said hydraulic cylinders is operatively connected to the valve system as aforesaid by the linkage 2 I, comprising a rod |23 to back-wash gate valves 21, 28 or 29, and the yoke |24, bell-crank pivoting on support |26, link |21, bell-crank |26 pivoting on support |29 and socket on lift-rod |3| secured to strainer valve 20.

In operation, the back-washing of the baskets |1, |6 and I9 is fully automatic and in a given sequence, as follows: Whenever the pressure differential between the inlet 9 and outlet |0 of the strainer reaches the point which has been found to indicate a detrimental clogging of the baskets, the alteration in the balance of inlet and outlet pressures upon the sealing fluid in the ringbody 30 of the pressure differential controller 2 causes said ring body 38 to swing as in Fig. 18 toward the low pressure or outlet side, or approximately from the position shown in dotted lines to the position shown in vfull lines, and the attached mercury switch 36 actuates the magnetic starter 31 of the motor 39. This operates the rotary oil pump 52 and at the same time through the gear reducer slowly turns the rotor 98 of the distributor valve 4 to direct the pumped oil to the lower end 6 of the first operating cylinder 5. The oil pressure in the lower end of said cylinder l lifts its piston (not shown) and thus actuai'es its above-described linkage 2| which closes the strainer valve' (not shown) and opens the back-wash gate, valve 21. Opening said backwash valve 21 relieves the water pressure in the first basket I1, and some of the strained water which has passed through the other two baskets |6 and I9 passes through the basket I1 to be back-washed, in the reverse direction, thus free- Said shaft 91 has its upperA 'ing the trssn that hss conecten on the inside wsu ofthe'basket l1 anddumpinsit'throughthsopen' bottom thereof. Gravel br other heavy waste will settle at the bottom of the said basket il and will be dumped likewise.

The angular spacing between ports I Il and I Y' of the distributor valve 4 is so arranged that the first basket will be back-washed for approximately 12 seconds. after which the oil pressure is applied to the upper end |Iof the operating.

cylinder I, the said piston is pushedl downward, its linkage 2| is actuated in the reverse direction sovthat the back-wash valve 21 closes and the strainer valve opens, and the first basket |1 returns to normal operation.

If the only substantialI amount of clogging had been in the nrst basket I1, now cleaned, the camoperated limit switch l will stop the pump mo;

tor 29 and terminate the back-washing, as the normal pressure dlil'erential across the strainer will have been restored by this ilrst back-washv the distributor valve l will proceed as above de.

scribed to direct the pumped oil in turn through the p'arts |05 and |00 to inlets Hl and ||0 of cylinder 0 respectively, raising and lowering the piston |22 to actuate through its linkage 2| its strainer valve 2l and back-wash gate valve 28 to back-wash the second basket Il; and if necessary, the distributor valve 4 will then direct oil through the ports |01 and |00 to inlets |20 and |2| of cylinder 1, raising and lowering its piston l|22 to actuate through its linkage 2| the strainer valve and back-wash gate valve 29 of the third basket I9.

From the foregoing description it will'be seen that the strainer is fully automatic, synchronized and economical, the nltered water being used for back-washing only when the baskets actually re quire it.

Although. I have hereinabove shown and described my invention in considerable detail, I do not wish to be limited narrowly to the exact and specific structure and arrangement stated, but I may use such substitutes. moditlcations or equivalents thereof as are within the scope and spirit of the invention and of the appended claims.

Having thus described my invention, what I.

claim as new and useful and desire to protect by Letters Patent is:

l. A fluid-straining apparatus comprising an outer casing having inlet and outlet pipes, a pressure chamber within said casing. a plurality of iter baskets therein. each basket having a normally open strainer v alve engaging therewith and a drain pipe and normally closed gate valve connected thereto, hydraulicl cylinder means operatively linked to said valves for simultaneously closing the strainer valve and opening. the. gate 2. A uuid-straining apparatus comprising a casing having inlet and outlet connections, horizontal and vertical partitions dividing the casing into an inner and anl outer chamber, the horivV aantal partition being provided with a plurality of openings, a cylindrical screen open at both ends and having its upper end supported in each such opening and extending downwardly with its bottom end in contact with the door 1n said inner chamber. a strainer/ valve at the upper end of each cylindrical'scree'n, drainage openings in the 'bottom of said inner chamber communicatin g with the bottom end ot each screen, a drain pipe connected at each drainage opening. a drain valve on each drain pipe, an external hydraulic cylinder for each screen so linked to its strainer valve anddraim valve as to close one valve when the other is ope'd, a source of fluid pressure, a rotary distributor valve having ports connecting said fluid pressure source with `the hydraulic cylinders in regular sequence, an electric motor operatively connected to said distributor valve, an electric current source connected to-said motor by a circuit including switch means, and `a pressure responsive mechanism connected between.

baskets open at each end and inserted vertically 'I through said orifices into the filtered-water chamber, a normally open strainer valve at the upper end of each filter basket, a plurality of drainage openings and a plurality of normally..

closed back-wash valves each communicating with the bottom end of a filter basket, a plurality of two-way hydraulic cylinders mounted outsidel the casing, each of said cylinders having a piston operatively linked to the valves of a filter basket,

a separate uid reservoir, a motor mounted thereon, a pressure diilerential responsive device oonnected between the inlet and outlet by suitable conduits and provided with means for starting the motor at a predetermined point. of pressure increase, a pump. coupled to said motor and conL nected to the reservoir, a distributor valve coupled through speed-reducingmeans to said motor and connected between the pump and 'the ends of the hydraulic cylinders, thereby closing the strainer valve and at the same time opening the back-wash valve of a illter basket and then Areversing the operation, for each filter basket in sequence.

4. A uid-straining apparatus comprising a casing having inlet and outlet connections, a plurality of filter baskets therein arranged to operate normally in parallel, a strainer valve located at the top of each basket, a back-wash valve communicating with the bottom of each basket, an

- `external operating cylinder for each baskt having a piston vconnected by linkage to the strainer valve and back-wash valve so that when one of said valves is open the other is closed, a separate reservoir for storing lluid fror the operating cylinders, a pump connected to said reservoir for forcing fluid therefrom, a distributor-,valve con- .nected to said pump for vreceivinguid therefrom and directing the uid through piping successively to each end of each operatingcylinder; to actuat'e the valves, reduction gearing operatively connected to said distributor valve, an eleccluding a normally open relay switch connected' to said motor, a`pressure diierential responsive device connected across the inlet and outlet connections by suitable conduits and having switch means thereon i'cr closing the relay switch when the pressure differential is increased by clogging, and a cam-operated limit switch operatively coupled to the gear reducer and connected toopen the circuit to the motor when the normal pressure diirerential-has been restored. I

WALTER, H. zomNGER.

8 REFERENCES CITED The following references are of record in the tlle of this patent:

UNITED STATES PATENTS Number Name Date 1,359,162 lGenter Nov. 16, 1920 1,883,805 Martin et al O ct. 18, 1932 2,041,048 Chesny May 19, 1936 2,066,479 MacIsaac Jan. 5, 1937 2,076,322 Pick Apr. 6, 1937 2,240,163 Pick Apr. '29, 1941 2,359,938 Quiroz Oct. 10, 1944 2,366,903

Harms et al Jan. 9, 1945 

